An electronic device such as a portable terminal is used as an information collection device that collects various types of information outdoors or as a wearable computer provided with various types of services. A typical electronic device includes a power switch used to turn on the power. When an electronic device is used outdoors, water or the like may enter the electronic device through the power switch, which is exposed from the electronic device. This may corrode metal portions such as terminals. Japanese Laid-Open Patent Publication No. 2006-86584 describes an electronic device including a receiver that receives radio waves to activate and deactivate a power supply in accordance with whether or not radio waves are received.
A receiver, such as that described above, receives radio waves from a corresponding transmitter but may also receive similar radio waves from other transmitters. Such radio waves produce noise in the receiver. This may activate or deactivate the power supply in an unintentional manner and cause erroneous operation of the electronic device. Thus, there is a need to reduce noise that causes erroneous operations.